Semiconductor Nanocrystals Photosensitize C60Crystals

Abstract
Semiconductor nanocrystals (SCNCs) made of CdSe, CdTe, and InP are used to photosensitize needlelike C60 crystals. The photocurrent is increased by up to 3 orders of magnitude as compared with C60 crystals without SCNCs. The photocurrent spectrum can be tuned precisely by the SCNC size and material, rendering the SCNC-functionalized C60 crystals an excellent material for spectrally tuneable photodetectors. We explain the increased photocurrent as a result of photoexcited electrons transferring from the SCNCs to the C60 crystals and causing photoconductivity, while the complementary holes remain trapped in the SCNCs.